Rackspace Public and Private Clouds
|Release||Document Status||DB Platform||Categories|
|3.8 or higher||INFO||All||Cloud Providers|
Rackspace offers many different managed services for cloud environments. This article explains their public cloud and private cloud behaviors and resources. It is best practice to identify which Rackspace environment ScaleArc is being deployed in.
Rackspace Public Cloud
The Rackspace public cloud runs on a Xenserver hypervisor environment that is multi-tennant and shared with all public cloud users. There are offerings for Standard and General Purpose vm instance types. Typically we should use the General Purpose vm instance types when deploying ScaleArc and allocate its resources appropriately for ScaleArc specs (ensure enough CPU for overhead, Memory for Cache, etc). In this environment most functionality is done through a self-service cloud portal that provides these point-and-click options to deploy a VM. Base OS images in this environment are managed and updated by Rackspace.
- For the CentOS images, there is a cron job that executes yum update regularly that should be disabled upon ScaleArc rpm installation, but double check. /etc/cron.*
- In this environment, it is possible to share a saved image from ScaleArc's rackspace account. Formal versions of ScaleArc images will be built when support for CentOS 6.7 is released.
- Users in this environment typically have Rackspace managing their database servers. The interaction is typically more hand-held and in conjunction with Rackspace Support.
- Rackspace public cloud doesn't support VIPs. ScaleArc HA users must use a TCP load balancer to configure active/passive HA.
Rackspace Private Cloud
The Rackspace private cloud environments offer a variety of hypervisors to choose from: Openstack, VMware, Hyper-V, they even resell AWS cloud. Customers who utilize Rackspace private cloud get most features of the public cloud, but do not have to share their resources. There is also flexibility in these environments to make changes at the VM level. For example: Configuring multi-core vCPUs - users have the abillity to define 4 sockets, 1 core per socket; or 2 sockets, 2 core per socket configurations. VM images can be customized and loaded via ISO or other install media, however, Rackspace will not support the custom image. This means the customer forfits all monitoring services and support that come with managed hosting. In most cases, a customer will not be willing to do this, so we must install via RPM.
- In this environment, it is best practice to provide system requirements upfront:
- CentOS 6.6 base OS (as of this writing)
- 4 core (2 Socket, 2 cores per socket)
- 4G memory minimum for production.
- 1TB disk mounted at /data for logs.
- /etc/fstab configured for read/write on all disks and directories
- Rackspace private cloud users may also have Racksapce managing their database servers, however the interaction has typically been hands off and more direct with the users than Racksapce support.
- Rackspace private cloud supports VIPs. These environments do not need a TCP load balancer and can configure ScaleArc active/passive HA through the UI.